Adding upstream version 3.40.1.upstream/3.40.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 510 insertions, 0 deletions

diff --git a/ext/misc/vtablog.c b/ext/misc/vtablog.c
new file mode 100644
index 0000000..424b345
--- /dev/null
+++ b/ext/misc/vtablog.c
@@ -0,0 +1,510 @@
+/*
+** 2017-08-10
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+**
+** This file implements a virtual table that prints diagnostic information
+** on stdout when its key interfaces are called.  This is intended for
+** interactive analysis and debugging of virtual table interfaces.
+**
+** Usage example:
+**
+**     .load ./vtablog
+**     CREATE VIRTUAL TABLE temp.log USING vtablog(
+**        schema='CREATE TABLE x(a,b,c)',
+**        rows=25
+**     );
+**     SELECT * FROM log;
+*/
+#include "sqlite3ext.h"
+SQLITE_EXTENSION_INIT1
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <string.h>
+#include <ctype.h>
+
+
+/* vtablog_vtab is a subclass of sqlite3_vtab which will
+** serve as the underlying representation of a vtablog virtual table
+*/
+typedef struct vtablog_vtab vtablog_vtab;
+struct vtablog_vtab {
+  sqlite3_vtab base;  /* Base class - must be first */
+  int nRow;           /* Number of rows in the table */
+  int iInst;          /* Instance number for this vtablog table */
+  int nCursor;        /* Number of cursors created */
+};
+
+/* vtablog_cursor is a subclass of sqlite3_vtab_cursor which will
+** serve as the underlying representation of a cursor that scans
+** over rows of the result
+*/
+typedef struct vtablog_cursor vtablog_cursor;
+struct vtablog_cursor {
+  sqlite3_vtab_cursor base;  /* Base class - must be first */
+  int iCursor;               /* Cursor number */
+  sqlite3_int64 iRowid;      /* The rowid */
+};
+
+/* Skip leading whitespace.  Return a pointer to the first non-whitespace
+** character, or to the zero terminator if the string has only whitespace */
+static const char *vtablog_skip_whitespace(const char *z){
+  while( isspace((unsigned char)z[0]) ) z++;
+  return z;
+}
+
+/* Remove trailing whitespace from the end of string z[] */
+static void vtablog_trim_whitespace(char *z){
+  size_t n = strlen(z);
+  while( n>0 && isspace((unsigned char)z[n]) ) n--;
+  z[n] = 0;
+}
+
+/* Dequote the string */
+static void vtablog_dequote(char *z){
+  int j;
+  char cQuote = z[0];
+  size_t i, n;
+
+  if( cQuote!='\'' && cQuote!='"' ) return;
+  n = strlen(z);
+  if( n<2 || z[n-1]!=z[0] ) return;
+  for(i=1, j=0; i<n-1; i++){
+    if( z[i]==cQuote && z[i+1]==cQuote ) i++;
+    z[j++] = z[i];
+  }
+  z[j] = 0;
+}
+
+/* Check to see if the string is of the form:  "TAG = VALUE" with optional
+** whitespace before and around tokens.  If it is, return a pointer to the
+** first character of VALUE.  If it is not, return NULL.
+*/
+static const char *vtablog_parameter(const char *zTag, int nTag, const char *z){
+  z = vtablog_skip_whitespace(z);
+  if( strncmp(zTag, z, nTag)!=0 ) return 0;
+  z = vtablog_skip_whitespace(z+nTag);
+  if( z[0]!='=' ) return 0;
+  return vtablog_skip_whitespace(z+1);
+}
+
+/* Decode a parameter that requires a dequoted string.
+**
+** Return non-zero on an error.
+*/
+static int vtablog_string_parameter(
+  char **pzErr,            /* Leave the error message here, if there is one */
+  const char *zParam,      /* Parameter we are checking for */
+  const char *zArg,        /* Raw text of the virtual table argment */
+  char **pzVal             /* Write the dequoted string value here */
+){
+  const char *zValue;
+  zValue = vtablog_parameter(zParam,(int)strlen(zParam),zArg);
+  if( zValue==0 ) return 0;
+  if( *pzVal ){
+    *pzErr = sqlite3_mprintf("more than one '%s' parameter", zParam);
+    return 1;
+  }
+  *pzVal = sqlite3_mprintf("%s", zValue);
+  if( *pzVal==0 ){
+    *pzErr = sqlite3_mprintf("out of memory");
+    return 1;
+  }
+  vtablog_trim_whitespace(*pzVal);
+  vtablog_dequote(*pzVal);
+  return 0;
+}
+
+#if 0 /* not used - yet */
+/* Return 0 if the argument is false and 1 if it is true.  Return -1 if
+** we cannot really tell.
+*/
+static int vtablog_boolean(const char *z){
+  if( sqlite3_stricmp("yes",z)==0
+   || sqlite3_stricmp("on",z)==0
+   || sqlite3_stricmp("true",z)==0
+   || (z[0]=='1' && z[1]==0)
+  ){
+    return 1;
+  }
+  if( sqlite3_stricmp("no",z)==0
+   || sqlite3_stricmp("off",z)==0
+   || sqlite3_stricmp("false",z)==0
+   || (z[0]=='0' && z[1]==0)
+  ){
+    return 0;
+  }
+  return -1;
+}
+#endif
+
+/*
+** The vtablogConnect() method is invoked to create a new
+** vtablog_vtab that describes the vtablog virtual table.
+**
+** Think of this routine as the constructor for vtablog_vtab objects.
+**
+** All this routine needs to do is:
+**
+**    (1) Allocate the vtablog_vtab object and initialize all fields.
+**
+**    (2) Tell SQLite (via the sqlite3_declare_vtab() interface) what the
+**        result set of queries against vtablog will look like.
+*/
+static int vtablogConnectCreate(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVtab,
+  char **pzErr,
+  int isCreate
+){
+  static int nInst = 0;
+  vtablog_vtab *pNew;
+  int i;
+  int rc;
+  int iInst = ++nInst;
+  char *zSchema = 0;
+  char *zNRow = 0;
+
+  printf("vtablog%s(tab=%d):\n", isCreate ? "Create" : "Connect", iInst);
+  printf("  argc=%d\n", argc);
+  for(i=0; i<argc; i++){
+    printf("  argv[%d] = ", i);
+    if( argv[i] ){
+      printf("[%s]\n", argv[i]);
+    }else{
+      printf("NULL\n");
+    }
+  }
+
+  for(i=3; i<argc; i++){
+    const char *z = argv[i];
+    if( vtablog_string_parameter(pzErr, "schema", z, &zSchema) ){
+      return SQLITE_ERROR;
+    }
+    if( vtablog_string_parameter(pzErr, "rows", z, &zNRow) ){
+      return SQLITE_ERROR;
+    }
+  }
+
+  if( zSchema==0 ){
+    *pzErr = sqlite3_mprintf("no schema defined");
+    return SQLITE_ERROR;
+  }
+  rc = sqlite3_declare_vtab(db, zSchema);
+  if( rc==SQLITE_OK ){
+    pNew = sqlite3_malloc( sizeof(*pNew) );
+    *ppVtab = (sqlite3_vtab*)pNew;
+    if( pNew==0 ) return SQLITE_NOMEM;
+    memset(pNew, 0, sizeof(*pNew));
+    pNew->nRow = 10;
+    if( zNRow ) pNew->nRow = atoi(zNRow);
+    pNew->iInst = iInst;
+  }
+  return rc;
+}
+static int vtablogCreate(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVtab,
+  char **pzErr
+){
+  return vtablogConnectCreate(db,pAux,argc,argv,ppVtab,pzErr,1);
+}
+static int vtablogConnect(
+  sqlite3 *db,
+  void *pAux,
+  int argc, const char *const*argv,
+  sqlite3_vtab **ppVtab,
+  char **pzErr
+){
+  return vtablogConnectCreate(db,pAux,argc,argv,ppVtab,pzErr,0);
+}
+
+
+/*
+** This method is the destructor for vtablog_cursor objects.
+*/
+static int vtablogDisconnect(sqlite3_vtab *pVtab){
+  vtablog_vtab *pTab = (vtablog_vtab*)pVtab;
+  printf("vtablogDisconnect(%d)\n", pTab->iInst);
+  sqlite3_free(pVtab);
+  return SQLITE_OK;
+}
+
+/*
+** This method is the destructor for vtablog_cursor objects.
+*/
+static int vtablogDestroy(sqlite3_vtab *pVtab){
+  vtablog_vtab *pTab = (vtablog_vtab*)pVtab;
+  printf("vtablogDestroy(%d)\n", pTab->iInst);
+  sqlite3_free(pVtab);
+  return SQLITE_OK;
+}
+
+/*
+** Constructor for a new vtablog_cursor object.
+*/
+static int vtablogOpen(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor){
+  vtablog_vtab *pTab = (vtablog_vtab*)p;
+  vtablog_cursor *pCur;
+  printf("vtablogOpen(tab=%d, cursor=%d)\n", pTab->iInst, ++pTab->nCursor);
+  pCur = sqlite3_malloc( sizeof(*pCur) );
+  if( pCur==0 ) return SQLITE_NOMEM;
+  memset(pCur, 0, sizeof(*pCur));
+  pCur->iCursor = pTab->nCursor;
+  *ppCursor = &pCur->base;
+  return SQLITE_OK;
+}
+
+/*
+** Destructor for a vtablog_cursor.
+*/
+static int vtablogClose(sqlite3_vtab_cursor *cur){
+  vtablog_cursor *pCur = (vtablog_cursor*)cur;
+  vtablog_vtab *pTab = (vtablog_vtab*)cur->pVtab;
+  printf("vtablogClose(tab=%d, cursor=%d)\n", pTab->iInst, pCur->iCursor);
+  sqlite3_free(cur);
+  return SQLITE_OK;
+}
+
+
+/*
+** Advance a vtablog_cursor to its next row of output.
+*/
+static int vtablogNext(sqlite3_vtab_cursor *cur){
+  vtablog_cursor *pCur = (vtablog_cursor*)cur;
+  vtablog_vtab *pTab = (vtablog_vtab*)cur->pVtab;
+  printf("vtablogNext(tab=%d, cursor=%d)  rowid %d -> %d\n", 
+         pTab->iInst, pCur->iCursor, (int)pCur->iRowid, (int)pCur->iRowid+1);
+  pCur->iRowid++;
+  return SQLITE_OK;
+}
+
+/*
+** Return values of columns for the row at which the vtablog_cursor
+** is currently pointing.
+*/
+static int vtablogColumn(
+  sqlite3_vtab_cursor *cur,   /* The cursor */
+  sqlite3_context *ctx,       /* First argument to sqlite3_result_...() */
+  int i                       /* Which column to return */
+){
+  vtablog_cursor *pCur = (vtablog_cursor*)cur;
+  vtablog_vtab *pTab = (vtablog_vtab*)cur->pVtab;
+  char zVal[50];
+
+  if( i<26 ){
+    sqlite3_snprintf(sizeof(zVal),zVal,"%c%d", 
+                     "abcdefghijklmnopqrstuvwyz"[i], pCur->iRowid);
+  }else{
+    sqlite3_snprintf(sizeof(zVal),zVal,"{%d}%d", i, pCur->iRowid);
+  }
+  printf("vtablogColumn(tab=%d, cursor=%d, i=%d): [%s]\n",
+         pTab->iInst, pCur->iCursor, i, zVal);
+  sqlite3_result_text(ctx, zVal, -1, SQLITE_TRANSIENT);
+  return SQLITE_OK;
+}
+
+/*
+** Return the rowid for the current row.  In this implementation, the
+** rowid is the same as the output value.
+*/
+static int vtablogRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
+  vtablog_cursor *pCur = (vtablog_cursor*)cur;
+  vtablog_vtab *pTab = (vtablog_vtab*)cur->pVtab;
+  printf("vtablogRowid(tab=%d, cursor=%d): %d\n",
+         pTab->iInst, pCur->iCursor, (int)pCur->iRowid);
+  *pRowid = pCur->iRowid;
+  return SQLITE_OK;
+}
+
+/*
+** Return TRUE if the cursor has been moved off of the last
+** row of output.
+*/
+static int vtablogEof(sqlite3_vtab_cursor *cur){
+  vtablog_cursor *pCur = (vtablog_cursor*)cur;
+  vtablog_vtab *pTab = (vtablog_vtab*)cur->pVtab;
+  int rc = pCur->iRowid >= pTab->nRow;
+  printf("vtablogEof(tab=%d, cursor=%d): %d\n",
+         pTab->iInst, pCur->iCursor, rc);
+  return rc;
+}
+
+/*
+** Output an sqlite3_value object's value as an SQL literal.
+*/
+static void vtablogQuote(sqlite3_value *p){
+  char z[50];
+  switch( sqlite3_value_type(p) ){
+    case SQLITE_NULL: {
+      printf("NULL");
+      break;
+    }
+    case SQLITE_INTEGER: {
+      sqlite3_snprintf(50,z,"%lld", sqlite3_value_int64(p));
+      printf("%s", z);
+      break;
+    }
+    case SQLITE_FLOAT: {
+      sqlite3_snprintf(50,z,"%!.20g", sqlite3_value_double(p));
+      printf("%s", z);
+      break;
+    }
+    case SQLITE_BLOB: {
+      int n = sqlite3_value_bytes(p);
+      const unsigned char *z = (const unsigned char*)sqlite3_value_blob(p);
+      int i;
+      printf("x'");
+      for(i=0; i<n; i++) printf("%02x", z[i]);
+      printf("'");
+      break;
+    }
+    case SQLITE_TEXT: {
+      const char *z = (const char*)sqlite3_value_text(p);
+      int i;
+      char c;
+      for(i=0; (c = z[i])!=0 && c!='\''; i++){}
+      if( c==0 ){
+        printf("'%s'",z);
+      }else{
+        printf("'");
+        while( *z ){
+          for(i=0; (c = z[i])!=0 && c!='\''; i++){}
+          if( c=='\'' ) i++;
+          if( i ){
+            printf("%.*s", i, z);
+            z += i;
+          }
+          if( c=='\'' ){
+            printf("'");
+            continue;
+          }
+          if( c==0 ){
+            break;
+          }
+          z++;
+        }
+        printf("'");
+      }
+      break;
+    }
+  }
+}
+
+
+/*
+** This method is called to "rewind" the vtablog_cursor object back
+** to the first row of output.  This method is always called at least
+** once prior to any call to vtablogColumn() or vtablogRowid() or 
+** vtablogEof().
+*/
+static int vtablogFilter(
+  sqlite3_vtab_cursor *cur,
+  int idxNum, const char *idxStr,
+  int argc, sqlite3_value **argv
+){
+  vtablog_cursor *pCur = (vtablog_cursor *)cur;
+  vtablog_vtab *pTab = (vtablog_vtab*)cur->pVtab;
+  printf("vtablogFilter(tab=%d, cursor=%d):\n", pTab->iInst, pCur->iCursor);
+  pCur->iRowid = 0;
+  return SQLITE_OK;
+}
+
+/*
+** SQLite will invoke this method one or more times while planning a query
+** that uses the vtablog virtual table.  This routine needs to create
+** a query plan for each invocation and compute an estimated cost for that
+** plan.
+*/
+static int vtablogBestIndex(
+  sqlite3_vtab *tab,
+  sqlite3_index_info *pIdxInfo
+){
+  vtablog_vtab *pTab = (vtablog_vtab*)tab;
+  printf("vtablogBestIndex(tab=%d):\n", pTab->iInst);
+  pIdxInfo->estimatedCost = (double)500;
+  pIdxInfo->estimatedRows = 500;
+  return SQLITE_OK;
+}
+
+/*
+** SQLite invokes this method to INSERT, UPDATE, or DELETE content from
+** the table. 
+**
+** This implementation does not actually make any changes to the table
+** content.  It merely logs the fact that the method was invoked
+*/
+static int vtablogUpdate(
+  sqlite3_vtab *tab,
+  int argc,
+  sqlite3_value **argv,
+  sqlite_int64 *pRowid
+){
+  vtablog_vtab *pTab = (vtablog_vtab*)tab;
+  int i;
+  printf("vtablogUpdate(tab=%d):\n", pTab->iInst);
+  printf("  argc=%d\n", argc);
+  for(i=0; i<argc; i++){
+    printf("  argv[%d]=", i);
+    vtablogQuote(argv[i]);
+    printf("\n");
+  }
+  return SQLITE_OK;
+}
+
+/*
+** This following structure defines all the methods for the 
+** vtablog virtual table.
+*/
+static sqlite3_module vtablogModule = {
+  0,                         /* iVersion */
+  vtablogCreate,             /* xCreate */
+  vtablogConnect,            /* xConnect */
+  vtablogBestIndex,          /* xBestIndex */
+  vtablogDisconnect,         /* xDisconnect */
+  vtablogDestroy,            /* xDestroy */
+  vtablogOpen,               /* xOpen - open a cursor */
+  vtablogClose,              /* xClose - close a cursor */
+  vtablogFilter,             /* xFilter - configure scan constraints */
+  vtablogNext,               /* xNext - advance a cursor */
+  vtablogEof,                /* xEof - check for end of scan */
+  vtablogColumn,             /* xColumn - read data */
+  vtablogRowid,              /* xRowid - read data */
+  vtablogUpdate,             /* xUpdate */
+  0,                         /* xBegin */
+  0,                         /* xSync */
+  0,                         /* xCommit */
+  0,                         /* xRollback */
+  0,                         /* xFindMethod */
+  0,                         /* xRename */
+  0,                         /* xSavepoint */
+  0,                         /* xRelease */
+  0,                         /* xRollbackTo */
+  0,                         /* xShadowName */
+};
+
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+int sqlite3_vtablog_init(
+  sqlite3 *db, 
+  char **pzErrMsg, 
+  const sqlite3_api_routines *pApi
+){
+  int rc;
+  SQLITE_EXTENSION_INIT2(pApi);
+  rc = sqlite3_create_module(db, "vtablog", &vtablogModule, 0);
+  return rc;
+}